Appendix 10.13 

Table 10-16 

Reference 6: 

Tables 18 and 19 on pages 22 and 23 and Table 29 on page 40 of 

"BART Application Analysis (AP-6041) for Dave Johnston Power 

Plant", May 28, 2009 
DEPARTMENT OF ENVIRONMENTAL QUALITY 

AIR QUALITY DIVISION 

BART Application Analysis 

AP-6041 

May 28, 2009 

NAME OF FIRM: PacifiCorp 

NAME OF FACILITY: Dave Johnston Plant 

FACILITY LOCATION: Sections 7 and 18, T33N, R74W 

 UTM Zone: 13 

 Easting: 436,592 m, Northing: 4,742,918 m 

 Converse County, Wyoming 

TYPE OF OPERATION: Coal-Fired Electric Generating Plant 

RESPONSIBLE OFFICIAL: Gary Slanina, Managing Director 

MAILING ADDRESS: 1591 Tank Farm Road 

 Glenrock, WY 82637 

TELEPHONE NUMBER: (307) 436-2001 

REVIEWERS: Cole Anderson, Air Quality Engineer 

Josh Nall, Air Quality Modeler 

PURPOSE OF APPLICATION:

Sections 169A and 169B of the 1990 Clean Air Act Amendments require states to improve visibility at 

Class I areas. On July 1, 1999, EPA first published the Regional Haze Rule, which provided specific 

details regarding the overall program requirements to improve visibility. The goal of the regional haze 

program is to achieve natural conditions by 2064. 

Section 308 of the Regional Haze Rule (40 CFR part 51) includes discussion on control strategies for 

improving visibility impairment. One of these strategies is the requirement under 40 CFR 51.308(e) for 

certain stationary sources to install Best Available Retrofit Technology (BART) to reduce emissions of 

three (3) visibility impairing pollutants, nitrogen oxides (NOx), particulate matter (PM), and sulfur 

dioxide (SO2). EPA published Appendix Y to part 51 - Guidelines for BART Determinations Under the 

Regional Haze Rule in the July 6, 2005 Federal Register to provide guidance to regulatory authorities for 

making BART determinations. Chapter 6, Section 9, Best Available Retrofit Technology was adopted 

into the Wyoming Air Quality Standards and Regulations (WAQSR) and became effective on December 

5, 2006. The Wyoming Department of Environmental Quality, Air Quality Division (Division) will 

determine BART for NOx and PM10 for each source subject to BART and include each determination in 

the §308 Wyoming Regional Haze State Implementation Plan (SIP). 
PacifiCorp Dave Johnston Plant 

AP-6041 BART Application Analysis 

Page 22

Table 16: Dave Johnston Unit 3 Economic Costs

Cost 

Existing 

Combustion 

Control 

Dry FGD 

with ESP 

Dry FGD with 

ESP and 

Polishing 

Fabric Filter 

Wet FGD 

with ESP 

Control Equipment Capital 

Cost $0 $91,499,734 $169,500,000 $144,300,464 

Capital Recovery Factor N/A 0.09513 0.09513 0.09513 

Annual Capital Recovery 

Costs $0 $8,704,370 $16,124,535 $13,727,303 

Annual O&M Costs $0 $4,455,188 $5,295,598 $6,044,908 

Annual Cost of Control $0 $13,159,558 $21,420,133 $19,772,211 

Table 17: Dave Johnston Unit 3 Environmental Costs

Existing 

Combustion 

Control 

Dry FGD 

with ESP 

Dry FGD with 

ESP and 

Polishing 

Fabric Filter 

Wet FGD 

with ESP 

SO2 Emission Rate (lb/MMBtu) 1.2 0.22 0.15 0.06

Annual SO2 Emission (tpy) (a) 13,316 2,428 1,656 662

Annual SO2 Reduction (tpy) N/A 10,888 11,660 12,654 

Annual Cost of Control $0 $13,159,558 $21,420,133 $19,772,211 

Cost per ton of Reduction N/A $1,209 $1,837 $1,563 

Incremental Cost per ton of 

Reduction N/A $1,209 $10,700 -$1,658 (b)

(a) Annual emissions based on unit heat input rate of 2,800 MMBtu/hr and 7,884 hours of operation per year. 

(b) Incremental cost from dry FGD with ESP and fabric filter is negative as a result of the lower annual cost of control for wet 

FGD with ESP. 

Table 18: Dave Johnston Unit 4 Economic Costs

Cost 

Existing 

Combustion 

Control 

Dry FGD with 

Full-scale 

Fabric Filter 

Wet FGD with 

Full-scale 

Fabric Filter 

Control Equipment Capital Cost $0 $243,100,000 $289,166,335 

Capital Recovery Factor N/A 0.09513 0.09513

Annual Capital Recovery Costs $0 $23,126,103 $27,508,393 

Annual O&M Costs $0 $5,318,117 $6,961,183 

Annual Cost of Control $0 $28,444,220 $34,469,576 
PacifiCorp Dave Johnston Plant 

AP-6041 BART Application Analysis 

Page 23

Table 19: Dave Johnston Unit 4 Environmental Costs

Existing 

Combustion 

Control 

Dry FGD with 

Full-scale 

Fabric Filter 

Wet FGD with 

Full-scale 

Fabric Filter 

SO2 Emission Rate (lb/MMBtu) 0.5 (a) 0.15 0.10

Annual SO2 Emission (tpy) (b) 8,081 2,424 1,616

Annual SO2 Reduction (tpy) 0 5,657 6,465

Annual Cost of Control $0 $28,444,220 $34,469,576 

Cost per ton of Reduction N/A $5,028 $5,332 

Incremental Cost per ton of 

Reduction N/A $5,028 $7,457

(a) 30-day rolling average SO2

 limit from Operating Permit 31-148-1 used as baseline. 

(b) Annual emissions based on unit heat input rate of 4,100 MMBtu/hr and 7,884 hours of operation per year. 

The cost effectiveness and incremental cost effectiveness of the proposed wet FGD and dry FGD controls 

for Units 3 and 4 are reasonable, except for the incremental cost effectiveness of installing a new 

polishing fabric filter with dry FGD on Unit 3. The final step in the SO2 BART determination process for 

Dave Johnston Units 3 and 4, Step 5: Evaluate visibility impacts, is addressed in a comprehensive 

visibility analysis presented in the next section of this BART application analysis. The Division 

evaluated the amount of visibility improvement gained from the application of additional NOx, PM/PM10, 

and SO2 emission control technology in relation to all three visibility impairing pollutants. Table 23 on 

page 34 and Table 24 on page 35 list the modeled control scenarios and associated emission rates. 

VISIBILITY IMPROVEMENT DETERMINATION: 

The fifth of five steps in a BART determination analysis, as required by 40 CFR part 51 Appendix Y, is 

the determination of the degree of Class I area visibility improvement that would result from installation 

of the various options for control technology. This factor was evaluated for the PacifiCorp Dave Johnston 

plant with an EPA-approved dispersion modeling system (CALPUFF) to predict the changes in Class I 

area visibility. The Division had previously determined that the facility was subject to BART based on 

the results of initial screening modeling using current (baseline) emissions from the facility. The 

screening modeling, as well as more refined modeling conducted by the applicant, is described in detail 

below. 

Wind Cave and Badlands National Parks (NP) in South Dakota are Class I areas located to the northeast 

of the plant at a distance of approximately 200 kilometers (km) and 290 km, respectively. Toward the 

south in Colorado, Rawah Wilderness Area (WA) and Mount Zirkel WA are both located approximately 

220 km from the plant, with Rocky Mountain NP located beyond Rawah WA.